Preheat the broiler.
Using a small paring knife, make a series of crosshatches to the cut surface of each eggplant half, cutting into the flesh but not through the skin.
In a medium bowl, combine the olives, capers, mint, and basil and mash lightly with a fork to make a coarse paste. Stir in salt and pepper, to taste, and the grated cheese and mix well. Press the mixture into the cuts in each eggplant.
Place the eggplants, cut side up, on a grill or broiler rack, and drizzle each with a bit of olive oil. Broil for about 8 minutes, or until the tops are crisp and bubbling. Serve at room temperature.